1. Field of the Invention
The present invention addresses the problems associated with hydraulic regenerative circuitry. By integrating unique valving and associated flow paths within a regenerative fluid system the performance of the system is greatly improved while the complexity and cost of the system is significantly reduced. Additionally, an improved regeneration reverse mode can now be employed which reduces the overall cycle time as compared to standard circuitry. Significantly, this system is more easily retrofitted to a standard hydraulic system which did not originally employ regeneration circuitry.
2. Description of the Related Art
Regenerative circuitry reduces cycle time for the forward motion of hydraulic cylinders. This is accomplished by externally directing the flow out of the rod end of a hydraulic cylinder and combining this flow with the flow from a supply pump, then directing this combined flow into the blind end of the cylinder. With prior art devices this process required that the external plumbing and valving associated with this flow path be greatly enlarged to handle the increased volume of fluid which must be transferred when utilizing a regenerative system. The cost of larger components and the labor required for their installation typically increased the expense of implementation of a retrofitted regenerative system beyond practicality.
Examples of related prior art are found in the following U.S. Pat. Nos. 3,476,014 to Churchill et al; 3,817,152 to Viron; 3,858,485 to Rosaen at al; 4,955,282 to Ranson; 4,375,181 to Conway; and 5,090,296 to Todd.